#include<stdio.h>
#include<sys/types.h>
#include<unistd.h>

int main()
{
    printf("I am parent process, pid:%d\n",getpid());

    pid_t ret = fork();
    while(1)
    {
        printf("up------------------------------------up\n");
        printf("ret:%d,pid:%d,ppid:%d\n",ret,getpid(),getppid());
        printf("down--------------------------------down\n");
        sleep(1);
    }
    return 0;
}
